The present invention relates in general to image processing apparatus and related processes, and in particular, to an image processing apparatus with a blower and preferably a cooler, and a related process for blowing preferably cool air down a conduit tube to a printhead at the other end, or vacuuming foreign particles from the printhead area through the conduit tube.
Pre-press color-proofing is a procedure that is used by the printing industry for creating representative images of printed material without the high cost and time that is required to actually produce printing plates and set up a high-speed, high volume, printing press to produce an example of an intended image. An image may require several corrections and be reproduced several times to satisfy or meet the customers requirements resulting in a large loss of profits and ultimately higher costs to the customer.
One such commercially available image processing apparatus is arranged to form an intended image on a sheet of thermal print media. Dye is transferred from a sheet of dye donor material to the thermal print media by applying a sufficient amount of thermal energy to the dye donor sheet material to form the intended image. This image processing apparatus generally includes a material supply assembly or carousel, and a lathe bed scanning subsystem or write engine, which includes a lathe bed scanning frame, translation drive, translation stage member, printhead, load roller, and imaging drum, and thermal print media and dye donor sheet material exit transports.
Operation of the image processing apparatus includes metering a length of the thermal print media (in roll form) from the material assembly or carousel. The thermal print media is then cut into sheet form of the required length and transported to the imaging drum. It is then registered, wrapped around, and secured onto the imaging drum. The load roller, which is also known as a squeegee roller, removes entrained air between the drum and the thermal print media. Next, a length of dye donor material (in roll form) is metered out of the material supply assembly or carousel, and cut into sheet form of the required length. It is then transported to the imaging drum and wrapped around it. A load roller is used to remove any air trapped between the imaging drum and the dye donor material. The dye donor material is superposed in the desired registration with respect to the thermal print media, which has already been secured to the imaging drum.
After the dye donor sheet material is secured to the periphery of the imaging drum, the scanning subsystem or write engine provides the scanning function. This is accomplished by retaining the thermal print media and the dye donor sheet material on the spinning imaging drum while it is rotated past the printhead to form an intended image on the thermal print media. The translation drive then traverses the printhead and translation stage member axially along the axis of the imaging drum in coordinated motion with the rotating imaging drum. These movements combine to produce the intended image on the thermal print media. The printhead is movable relative to the longitudinal axis of the imaging drum.
A number of laser diodes are tied to the printhead and can be individually modulated to supply energy to selected areas of the thermal print media in accordance with an information signal. The printhead includes a plurality of optical fibers coupled to the laser diodes at one end, and at their opposite ends to a fiber optic array within the printhead. The printhead is movable relative to the longitudinal axis of the imaging drum. The dye is transferred to the thermal print media as the radiation, which is transferred from the laser diodes by the optical fibers to the printhead and thus to the dye donor sheet material, is converted to thermal energy in the dye donor sheet material.
After the intended image has been formed on the thermal print media, the dye donor sheet material is removed from the imaging drum without disturbing the thermal print media beneath it. The dye donor sheet material is then transported out of the image processing apparatus. Additional dye donor sheet materials are sequentially superimposed with the thermal print media on the imaging drum, further producing an intended image. The completed image on the thermal print media is then unloaded from the imaging drum and transported to an external holding tray on the image processing apparatus.
Although the presently known and utilized image processing apparatus is satisfactory, it is not without drawbacks. Images, and the apparatus itself over time, can be contaminated or blocked by dust or small particles generated by the imaging process. Temperatures in many image processing apparatus can get very hot, sometimes approaching several hundred degrees Fahrenheit. With the present apparatus, the printhead area can be cooled, and dust and other particles in the area can be reduced, thus decreasing contamination and improving overall image quality.
Also, the present invention can be extended to cover an image: processing device that utilizes more than one imaging station, such as a printing press, where each station images a different plate used to produce a different color. With such a design, it is important that each station be controlled thermally, in some cases capable of skiving material, and kept free of foreign material to provide the proper image quality. Minor changes in the printhead due to thermal effects or foreign material can lead to objectionable effects in the output image.
The present invention is an image processing apparatus for forming images on a thermal print media, comprising: a) a rotatable drum; b) a motor for rotating the drum; c) at least one movable printhead external to the drum; d) thermal print media removably mounted on the drum, the printhead being positioned to move over the thermal print media on the drum; e) an imaging assembly; f) at least one connection means for connecting the imaging assembly to the printhead; g) at least one conduit tube for conducting the connection means between the imaging assembly and the printhead, one end of the conduit tube being affixed to the printhead, an opposite end of the conduit tube being connected to the imaging assembly; and h) an air moving device connecting directly or indirectly to the conduit tube at the opposite end of the conduit tube. The air moving device may be a cooler, a positive air blower, and/or a vacuum blower. A process for eliminating foreign particles from the printhead area is also included herein.
Advantages of the present invention include one or more of the following: 1) cooling the printhead to protect against adverse effects of high temperatures; 2) allowing a straightforward method of removing material skived from the thermal media to form the intended image; 3) preventing foreign material and other undesirable particles from contaminating the printhead; 4) working within existing designs for the writing drum and for imaging support subsystems without major redesign of existing systems to achieve these benefits; 5) vacuuming foreign particles away from the apparatus in a manner which allows proper disposal of contaminants; 6) improving output of the intended image; and 7) allowing these advantages for multiple stations in the case of a printing press, for example.